Project properties

Title Initiation of fruiting body formation in Oyster mushroom on a commercial farm
Group Plant Breeding, Laboratory of
Project type thesis
Credits 24-36
Supervisor(s) Johan Baars en Arend van Peer
Examiner(s) Johan Baars en Arend van Peer
Contact info en
Begin date 2021/09/01
End date 2022/01/31
Description WUR Plant Breeding has developed non-sporulating varieties of Oyster mushroom. This has meant a huge improvement of the working conditions in this industry, as inhaling basidiospores of this mushroom on a daily basis can cause lung problems. As a result these varieties have quickly been adopted by the industry. As can be seen on the pictures below, Oyster mushrooms are grown on blocks of about 17-18 kg pasteurized wheat straw. These are wrapped in a micro-perforated plastic in which bigger holes are punched to allow for the development of fruiting bodies. These blocks are inoculatedwith cereal grains or similar carriers that are pre-colonized with the mycelium (spawn). After about 17 days the blocks are fully colonized by the Oyster mushroom mycelium. At that point in the cultivation cycle, the formation of fruiting bodies needs to be initiated. Formation of fruiting bodies is governed by light, a drop in temperature and a drop in CO2 concentration in the air. Once pins or primordia (the initials of the fruiting bodies) are formed, a grower is well able to predict when the mushrooms will be ready for harvest.
Ideally all blocks of substrate should produce pins simultaneously. However, as can be seen in the left picture, not all blocks develop pins simultaneously, causing delay in harvest or reduction in yield. Currently it is unknown why this happens. Our hypothesis is that not all conditions for proper initiation of mushroom formation are met.
We are offering a master thesis topic to investigate this phenomenon in on-farm research on a mushroom farm in the eastern part of the province of Brabant (45 minute drive by car from Wageningen). A student will perform a literature study to collect available knowledge on induction of fruiting body formation. Next to this the student will accurately monitor the process of substrate cultivation and induction of pinning. Substrate colonization will (amongst others) be followed by monitoring the drop in pH of the substrate. Furthermore a method needs to be developed to accurately monitor pinning.
Subsequently the student will determine the effects of varying environmental cultivation factors such as timing of light induction, color of light used, speed of changing the temperature and CO2 concentration in the air, levels to which temperature and CO2 concentration are changed, etc.
As a separate part of the project, the student is encouraged to develop a mass balance (change in substrate dry matter) for the cultivation of Oyster mushrooms to see if differences in the utilization of the substrate by the mushroom may be involved.
Used skills
Requirements in possession of a driving licence; Advanced Courses PhP50306